1. Field of the Invention
This invention relates to an articulated arm for holding a tool.
2. Description of the Prior Art
Recently, various kinds of tools are utilized in the medical field. For example, in the field of brain surgery a tool referred to as brain spatula is used. The brain spatula is used for pressing the brain partly during brain surgery to provide wider vision of the site to be operated. The brain spatula is held immovably by a special holding arm with the brain being pressed by the brain spatula, and if the force of the holding arm to hold the brain spatula is insufficient, the brain spatula is pushed back gradually by the brain during the operation. Accordingly, the location of the brain spatula must be adjusted occasionally. Even if the holding arm has sufficient holding force, the position or angle of the brain spatula must frequently be changed for convenience's sake during the surgery. Thus, the brain spatula holding arm should have such operability as to quickly respond to such frequent changes.
That is, the holding arm for holding a tool such as a brain spatula is required to have a function of holding a tool securely at a desired position with no reduction in the holding force with time and allowing easy change of the holding position. Incidentally, medical tools which are to be held by such holding arm include any conceivable tools and devices, in addition to brain spatulas, such as an aspiration tube, an ultrasonic echo probe and an endoscope. Further, there are innumerable tools and devices which also require such secured holding in other fields than medicine.
The present inventor accomplished the present invention noting such prior art technique and provides an articulated tool holding arm which functions as described above.